So we're doing a 73 restoration project

[Patcon]

3 hours ago, darom said:

I have one of those $3.99 Harbor Freight mirror tools (what is left of it). Just be careful extending it too far - I was inspecting one of my 04 Ford's powerstroke's cylinder heads (valve cover removed, injectors and high pressure oil rail out) when the telescopic tube got disconnected and I dropped 2 metal little flat plates down my engine. I found one. The other ended up in my IPR valve blowing a hole through its metal screen. These plates are used in the H&F tool to hold telescopic pieces together.

Ouch!! I hate to tear up the diesel and the parts aren't cheap.

[Michaelwk]

Alright, I finally got chance to work on the carbs today.  Tried to pull out the float pin with a tweezers but no luck.  That sucker is in there tight.  Let it soak in some carb cleaner few times and still nothing.  Took apart the power valve and cleaned that as well.  Realized one of the two rebuild kits I got from rockauto didn’t have the valve diaphragm I needed… not a huge deal since the other kit did have it, and I only got through the front carb today.  But I did freak out a bit thinking I had the wrong kit somehow. 

I gave the fuel window a good cleaning too from the outside.  I would have liked to clean the inside too but the float bowl is in the way.  After reassembling and filling it up, it actually looks like the fuel is at the top of the window, rather than in the center.  I am assuming the carbs sits perfecting level in the car, right?  If it was tilted toward the rear of the engine bit, the fuel level would be better.  Looking at the car it was hard to tell as it is on jacks and not perfectly level.  Assuming the level is too high, could this be a worn needle valve?  Or sunk float?

I’m thinking maybe just tear out the float and buy a new one.  That would allow me to get a pliers around that pin and push it out.  New float bowl is only $30 on ebay.

[Captain Obvious]

Of course the final check should be done with the carbs installed in the engine bay, but they sit pretty much level when attached to the engine. With that in mind, for bench testing you can stand them upright level and use that as a guide.

And yes, if they are filling to the top of the window, that's a problem. My first guess would be small piece of debris partially holding the needle valve open a little bit and requiring more than desired force to get it to close shut completely. Other possibilities are the usual suspects. Worn needle,. Rubber tipped needle that has taken a set or has shrunk. Damaged or soaked float. Needle valve spring that has taken a set. etc...

You really need to get the float out to diagnose, but I would hate to see you ruin a float to get that pin out. Not proud to admit it, but I've done it. I think if I had more time (at the time) I could have eventually gotten it out without destroying the float, but I was pressed for time. Maybe a little heat on the pin with one of those pinpoint butane torches? I don't remember if I tried that on mine, but it might help?

[Captain Obvious]

Have you tried getting the pin to move using a razor knife next to the float hinge?

[Captain Obvious]

12 hours ago, siteunseen said:

I want one!  As my eyesight gets a little fuzzier everyday. ?

I worry what you would do with such a device.....

[Michaelwk]

Yeah, I was thinking of using heat as well.  That Rusty nut remover that was linked previously might be a good choice.  I think I'll stay away from torches with fuel in the vicinity.  Probably have to keep the heat away from the floats though... don't want those to soften and warp.  Could be tricky...

I did try the razor blade as well with no success.

Will think on this one for a while.  Ruining the float will be the last resort. 

[Captain Obvious]

Haha! I was figuring the carb was open and dry enough that I wasn't worried about fuel still inside. Sure, if it's still got fuel in it, then a torch would be tricky. But I was figuring it was dry. And yes, you would have to keep the heat away from the plastic floats themselves. I was figuring you could maybe get a little heat on the short stub of the end part of the pin that protrudes out into the hole. That and maybe some on the carb body itself from the outside at the blind end of the pin.

And that rusty nut remover is an induction heater and I really doubt you could get the coil down into the hole far enough to have any impact on the pin.

If I were to go through this again, I would probably drill a small access hole through the carb body to the blind end of the pin and use a small rod to push the pin out from that end. Essentially complete the pin hole all the way through both sides of the carb body. Then tap the new hole for threads and run a loctited plug screw into the hole to seal it.

And, I've already fixed this problem on the last set of flat tops I worked on so it would never happen again. I made new float pins that are maybe a quarter inch longer than the original ones so there is a lot more material to grip to pull them out. Then I bored out the sealing caps to include a recessed area in the middle to account for the longer pins. Here's a couple pics.

Longer pin with much more to grab:

And the recess in the cap to account for the additional length:

For a fee, I may be persuaded to repeat that procedure.    

[Captain Obvious]

@Zup, You might be interested in the above as well. It's another one of the non-visible mods that I have done to the anchors.

[Michaelwk]

Good news!  Letting that pin sit in some carb cleaner long enough got it loose.  Got the utility knife blade in there next to the float like you mentioned @Captain Obvious and was able to push it out and grab it with the tweezers.  I like your new float pins!  I've got a machine shop at work, maybe I can talk one of the guys into making me a couple new pins and modifying the cap like yours.

Started on the second carb tonight as well.  Again the pin is quite stuck.  Will give it a few rounds of carb cleaner and try again in a few days. 

Comparison pic of the old valve seat (left) and new one from the rebuild kit.  The pic doesn't show the exact height of the valve as they were a little closed, but the new one does seem a bit longer.  Will have to adjust that tang on the float maybe.  Going to wait until I have both carbs ready and then redo the fuel level measurements.

[Captain Obvious]

Excellent. Glad you got that first float pin out, and I hope you have the same success with the second.  

So, if you modify the carbs like I did, make sure your machinist understands that the access cap holds the pin in place and prevents if from slipping out of it's mounts. In other words... Once the cap is screwed tight into place, there needs to be a tiny amount of side to side play in the pin, but not nearly enough that it can slip out of either hole in the carb body.

Too short and the pin will be able to slip out of a hole and the float can come loose on one side.
Too long and the pin will punch through the cap when you tighten it down.

Don't do either of those.

And if you have someone make a new pin, they'll need some precise diameter sized metric rod stock for the pin. Use something already ground to size unless you have a centerless grinder at your disposal.

As for the needle valves, you won't really know if there's any difference until you get things put back together again. Might be fine, or you might have to adjust the float tang.

[Michaelwk]

Alright, another positive update.  Managed to get the second float pin out today, cleaned up the dirty parts of the second carb and replaced the power valve gaskets and needle valve.  Got my replacement rebuild kit on Friday but another disappointing find regarding it, the float cover gasket swells after coming into contact with fuel... so trying to reuse it is a PITA.  Was able to get it back into the groove once, but couldn't the second time.  Just reused the original gasket.  I doubt you can buy those outside of the kit, so we'll just hope the old gasket still works for now.

Adjusted the tangs on the floats to get the fuel level into the middle of the window and meet the dimensions from the FSM.  I was surprised how far off they were from the recommended dimensions.  I wonder if the floats were replaced before and just half-arse adjusted. 

Managed to get the carbs back on the engine, even with the one busted hose. Just stretched it a bit to reach.  Anybody have a good source for random hoses?  The specific one I need is the air bypass hose that runs between the two carbs.  Has a couple sharp bends, so I don't know that a regular straight hose would work.

After getting the air cleaner back on, I gave her some choke and it fired up!

Checked quick and no oil or fuel leaks were immediately present and the oil pressure was right in the middle of the gauge.  Tried to put the choke down a little and it died.  Started up again and saw there was a good bit of white smoke coming out the tail pipe.  The engine also sounded a bit louder than I thought it should so I turned it off.  Next up I think I'm going to do a compression test and see how things are looking.

Did not get a chance to try and see the fuel level with a mirror while the car was running but that's ok, not looking to do any fine tunes right now.  Just happy that it finally ran.

[Michaelwk]

On 10/31/2018 at 9:06 AM, Captain Obvious said:

Excellent. Glad you got that first float pin out, and I hope you have the same success with the second.  

So, if you modify the carbs like I did, make sure your machinist understands that the access cap holds the pin in place and prevents if from slipping out of it's mounts. In other words... Once the cap is screwed tight into place, there needs to be a tiny amount of side to side play in the pin, but not nearly enough that it can slip out of either hole in the carb body.

Too short and the pin will be able to slip out of a hole and the float can come loose on one side.
Too long and the pin will punch through the cap when you tighten it down.

Don't do either of those.

And if you have someone make a new pin, they'll need some precise diameter sized metric rod stock for the pin. Use something already ground to size unless you have a centerless grinder at your disposal.

As for the needle valves, you won't really know if there's any difference until you get things put back together again. Might be fine, or you might have to adjust the float tang.

Thanks for the advice on the new pin.  I didn't get a chance to take the pin and screw into work, but I think we should have some metric rod stock to use.